2. in the 24 hours following surgery for postoperative intra-abdominal infection (defined as gross pus or purulent effusion within the peritoneal cavity or in one or several collections). Postoperative infection will be defined as an infection observed in a delay of 60 days following a procedure (endoscopy, surgery (abdominal, urologic, gynecologic or vascular surgery or any surgery performed in the peritoneal or retroperitoneal space) or interventional radiology)